Mysql的安装错误：无法为MySQL的“根”用户

Question

很多人都遇到过这样的错误设置的密码，但没有提供解决方案，为我的情况下工作：

在我的Ubuntu 14.04服务器，MySQL服务器5.5优良工程，出于某种原因，我们两个人试图升级到5.6，经过一些混乱的操作，失败了，只有5.6客户端和mysql-commn被安装了，所以我其实不知道他们的详细操作，然后我尝试了降级到5.5这样的：

killall -9 mysql 
killall -9 mysqld 
apt-get purge mysql-* 
remove /etc/myql 
apt-get install mysql-sever-5.5 

得到了一个错误：

┌───────────────────────Configuring mysql-server-5.5─────────────────────────┐ 
│ Unable to set password for the MySQL "root" user       │ 
├────────────────────────────────────────────────────────────────────────────┤ 

和安装日志是这样的：

Setting up mysql-server-core-5.5 (5.5.54-0ubuntu0.14.04.1) ... 
Setting up mysql-server-5.5 (5.5.54-0ubuntu0.14.04.1) ... 
170218 2:15:57 [Warning] Using unique option prefix key_buffer instead of key_buffer_size is deprecated and will be removed in a future release. Please use the full name instead. 
170218 2:15:57 [Note] Ignoring --secure-file-priv value as server is running with --bootstrap. 
170218 2:15:57 [Note] /usr/sbin/mysqld (mysqld 5.5.54-0ubuntu0.14.04.1) starting as process 9038 ... 
start: Job failed to start 
invoke-rc.d: initscript mysql, action "start" failed. 
dpkg: error processing package mysql-server-5.5 (--configure): 
subprocess installed post-installation script returned error exit status 1 
Processing triggers for libc-bin (2.19-0ubuntu6.7) ... 
Errors were encountered while processing: 
mysql-server-5.5 
E: Sub-process /usr/bin/dpkg returned an error code (1) 

错误日志是这样的：

170218 2:15:57 [ERROR] /usr/sbin/mysqld: Incorrect information in file: './mysql/tables_priv.frm' 
ERROR: 1033 Incorrect information in file: './mysql/tables_priv.frm' 
170218 2:15:57 [ERROR] Aborting 

170218 2:15:57 [Note] /usr/sbin/mysqld: Shutdown complete 

170218 2:15:57 [Warning] Using unique option prefix myisam-recover instead of myisam-recover-options is deprecated and 
will be removed in a future release. Please use the full name instead. 
170218 2:15:57 [Note] Plugin 'FEDERATED' is disabled. 
170218 2:15:57 InnoDB: The InnoDB memory heap is disabled 
170218 2:15:57 InnoDB: Mutexes and rw_locks use GCC atomic builtins 
170218 2:15:57 InnoDB: Compressed tables use zlib 1.2.8 
170218 2:15:57 InnoDB: Using Linux native AIO 
170218 2:15:57 InnoDB: Initializing buffer pool, size = 128.0M 
170218 2:15:57 InnoDB: Completed initialization of buffer pool 
InnoDB: Error: log file ./ib_logfile0 is of different size 0 50331648 bytes 
InnoDB: than specified in the .cnf file 0 5242880 bytes! 
170218 2:15:57 [ERROR] Plugin 'InnoDB' init function returned error. 
170218 2:15:57 [ERROR] Plugin 'InnoDB' registration as a STORAGE ENGINE failed. 
170218 2:15:57 [ERROR] Unknown/unsupported storage engine: InnoDB 
170218 2:15:57 [ERROR] Aborting 

170218 2:15:57 [Note] /usr/sbin/mysqld: Shutdown complete 

那么，如何解决这个问题的任何建议表示赞赏？

Answer 1

这样做：

sudo -i 
service mysql stop 
killall -KILL mysql mysqld_safe mysqld 
apt-get --yes purge mysql-server mysql-client 
apt-get --yes autoremove --purge 
apt-get autoclean 
deluser --remove-home mysql 
delgroup mysql 
rm -rf /etc/apparmor.d/abstractions/mysql /etc/apparmor.d/cache/usr.sbin.mysqld /etc/mysql /var/lib/mysql /var/log/mysql* /var/log/upstart/mysql.log* /var/run/mysqld 
updatedb 
exit 

您可能还需要dpkg -l | grep mysql列出任何mysql安装包，然后如每个条目为sudo apt-get purge mysql-common。

如果上述步骤完成后，并没有mysql引用那里当dpkg -l | grep mysql运行，你可以尝试用以下命令进行安装：

sudo apt-get install mysql-sever-5.5 

Answer 2

我面对在Ubuntu 16.04安装MySQL的5.6版相同的问题LTS。在与朋友搜索和交谈之后，我想出了如何安装这个没有错误。

首先备份数据库，并按照这个命令：

$ sudo apt-get remove --purge *mysql/* 
$ sudo apt-get autoremove 
$ sudo apt-get autoclean 
$ sudo rm -rf /var/lib/mysql 
$ sudo apt install mysql-server-5.6 
$ sudo apt install mysql-client-5.6